1. Field of the Invention
This invention relates to a method of reclaiming photographic couplers from an aqueous emulsified dispersion which contains photographic couplers dissolved in a low-volatile organic solvent (hereinafter referred to as coupler solvent oil) or from a coating waste containing such an emulsified dispersion. Both emulsified dispersions and coating wastes containing emulsified dispersions are hereinafter referred to as emulsions for simplicity.
2. Description of the Prior Art
As is quite well known in the art, a photographic coupler is dissolved in a low-volatile organic solvent and the resultant solution is dispersed into an aqueous hydrophilic colloid solution, e.g., an aqueous gelatin solution, which is then used to produce a layer in a light-sensitive photographic material.
From an industrial standpoint, desirably a coupler reclaiming method must be able to provide couplers which exhibit the same photographic characteristics as those initially provided by couplers with a reasonable cost of reclamation. The latter condition self-evidently means a high reclamation efficiency.
In order to reclaim a coupler dissolved in a coupler solvent oil, it is necessary to separate the coupler from the coupler solvent oil. In the past, however, no methods are known for such a separation which can be conducted with a high efficiency. Accordingly, coupler reclamation has been economically unprofitable, and rather than reclaim the couplers dissolved in a coupler solvent oil, the mixture has always been discarded.